John Mckone was commissioned a 2nd Lieutenant in the United States Air Force on July 31, 1954.

During the summer of 1960, John was the navigator on an RB47 reconnaissance aircraft based out of Forbes Field in Topeka, Kansas. He and his fellow air crew were deployed to England, and on one fateful mission his aircraft was shot down by Soviet fighters on July 1, 1960. Earlier that year, Frances Gary Powers had been shot down while flying a U2 cold war reconnaissance mission over the Soviet Union, so tensions were high between the United States and the Soviets.

As a Prisoner of War, he and the only other survivor from his aircraft, then Captain Freeman B. Olmstead, spent almost seven months in the infamous Lubyanka prison. Both were released from captivity on January 24, 1961.

In 1962, their ordeal was captured in an account by William Lindsay White, entitled, The Little Toy Dog: The story of the two RB-47 flyers, Captain John R. McKone and Captain Freeman B. Olmstead. He found himself on the cover of Time Magazine, and met with President John F. Kennedy. Upon their return, he and Olmstead were greeted as American heroes.

John was awarded the Silver Star for actions during the Cold War between July 1, 1960-January 24, 1961. Because of the sensitivity of his mission, he did not receive the award until later on in his career.

In addition to the Silver Star, John was the recipient of the Legion of Merit, the Distinguished Flying Cross and the POW medal.